The rail service, judicial authorities and France's BEA safety agency would each be investigating.

Passenger Marc Cheutin, 57, said he had to "step over a decapitated person" after the accident to exit the carriage he had been travelling in.

"Shortly after departure, just as I was getting into my book, we felt a first shock that shook the carriage I was in.

"Then there was a second shock and the carriage lifted up, then a third and a fourth and the carriage went over on its side."

A witness who had been waiting for a train at the station, Vianey Kalisa, said: "I saw a lot of wounded people, women and children trapped inside.

"I was shaking like a child. People were screaming. One man's face was covered in blood. It was a like a war zone."

Dazed survivors stood near mangled wagons

In the immediate aftermath of the accident, dazed survivors, some in blood-stained clothing, stood near mangled train wagons and the crushed remains of a station platform.

Director of security at SNCF Alain Krakovitch praised the quick reaction of the train driver.

"He felt jolts entering the station and applied the regulation measures in the space of a few seconds, which is to say a radio warning signal and a light warning signal", thus stopping all traffic in the area.